is 8 grams a lot?

im not super active in this sub and i dont frequently do nitrous but i just saw a post of someone asking is 4 grams too much and now im confused. the few times i did nitrous i did like a 8 gram cartridge and nearly inhaled all 8 grams in one hit, do i just have a tolerence or something? that would explain why nitrous at the dentist barely effects me, speaking of nitrous as the dentist does anyone know there procedure for administration of nitrous and how much exactly is in one inhalation?